And what is sports these days? The president of the United States is speaking of sports from the bully - and I guess I do mean bully - pulpit and tragic football news this week. NPR's Tom Goldman joins us.

Tom, thanks for being with us. We've got a lot of stuff breaking live in the sports world, and none of it involves anything on the field.

TOM GOLDMAN, BYLINE: Right.

SIMON: As we've been on the air today, President Trump tweeted, going to the White House is considered a great honor for a championship team. Stephen Curry is hesitating. Therefore, invitation is withdrawn - which I know I doubt that any Golden State Warrior is going to show up now.

Now, this follows the president's attack last night on Colin Kaepernick and other NFL players in language I won't repeat. They've made quiet demonstrations during the national anthem. And all this from the former owner of the New Jersey Generals football team, not one of the great franchises in history, who also said that he's tired about hearing about concussion and brain damage in football. Tom, I'm breathless (laughter). What do you make of all this high-level invective, if not necessarily high-minded, in sports?

GOLDMAN: I guess kind of an overall statement I can make, Scott, is this idea that sports and politics don't mix is officially dead, courtesy of the president. Let's go back to his NFL comments last night about the guys who've protesting the national anthem. This is just a guess. But since the president referred to those protesters as SOBs, I'd think some may not take too kindly. I don't think this is going to silence anyone. In fact, I predict it will fuel protests.

The president also said, as you alluded to, that referees are ruining the game by calling penalties for, quote, "beautiful tackles." And he used visuals, bringing his fists together as in a collision, collisions of course, Scott, that are being shown to wreak havoc with players' brains. Now, early this morning (laughter) - the tweet storm - the head of the players union, DeMaurice Smith, tweeted a statement that was prefaced by the words, we will never back down. We no longer can afford to stick to sports. The statement said in part, the union will never back down when it comes to protecting the constitutional rights of our players as citizens as well as their safety as men who compete in a game that exposes them to great risks.

Now, also, NFL Commissioner Roger Goodell said in a statement - I'm quoting here - "divisive comments like these demonstrate an unfortunate lack of respect for our great game and all of our players and a failure to understand the overwhelming force for good our clubs and players represent in our communities." Now, Scott, as you know, Roger Goodell works for the owners, several of whom are supporters and former financial contributors to Donald Trump.

SIMON: I also want to add a tweet that I - we saw from Colin Kaepernick's mother. I can't repeat every word in it. She said, quote, "guess that make me a proud" - the B-word. And I don't mean bumblebee.

GOLDMAN: (Laughter).

SIMON: The concussions, the president doesn't want to talk about. This happens in a week when, tragically, researchers at Boston University said Aaron Hernandez - who was in prison for murder, took his own life and had advanced stage CTE brain damage.

GOLDMAN: Yeah. You know, I don't think this it's a surprise to people who followed this case. It's more sobering news for a league that, I think it's safe to say, is dealing with a CTE crisis, although there's still a lot of science to be done to determine how prevalent this brain disease is in football players.

Now, Hernandez's lawyers have filed a lawsuit against the NFL and the New England Patriots, Aaron's former team. But that may not go anywhere. The major concussion lawsuit involving thousands of former NFL players, which has been settled - and payments are going out to players right now - if players previously opted out of that settlement, they had the right to file their own lawsuits against the league. But Hernandez reportedly did not opt out several years ago, meaning his lawyers, in fact, might not have the right to file this lawsuit.

SIMON: I'm hoping there will be more attention from here on out to the fact that people with CTE might not be just harming themselves but of course they pose a threat to others, everyone around them.

GOLDMAN: Yeah. You know, there is not a straight line - it hasn't scientifically proved that CTE is related to violence toward others, including women. But of the players who do get arrested - and they get arrested at a much lower rate than the general population their age - there's alarmingly high percentage of those arrested for domestic violence. So a very troubling aspect of a very troubling problem.